Radio-frequency module and wireless device

ABSTRACT

A wireless device includes a radio-frequency module, a modem module, and a control unit. The radio-frequency module and the modem module operate either in a first operation mode or in a second operation mode. The control unit, coupled to the RF and the modem module, generates a control signal to indicate to the RF and the modem module to operate in the first operation mode or to operate in the second operation mode. A first set of signal formats corresponding to the first operation mode is a superset of a second set of signal formats corresponding to the second operation mode, and a first power consumption corresponding to the first operation mode is higher than a second power consumption corresponding to the second operation mode.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional application No.62/409,888, filed on Oct. 19, 2016 and incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present disclosure relates to a radio-frequency module and awireless device, and more particularly, to a radio-frequency module anda wireless device capable of reducing power consumption thereof.

2. Description of the Prior Art

Bluetooth is a Personal Area Network (PAN) standard for wirelesscommunications between Bluetooth enabled communication devices. Thistechnology eliminates cables and wires between devices, facilitates bothdata and voice communication, and enables ad-hoc networks betweenvarious Bluetooth devices.

Bluetooth devices are usually powered by batteries, such that Bluetoothdevices are required to consume less electricity power. In addition,some Bluetooth devices are expected to provide higher data rate and/orbetter performance. However, the Bluetooth devices providing higher datarate and/or better performance would consume more power. Therefore, howto maintain data rate and/or performance and to further reduce powerconsumption is a significant objective in the field.

SUMMARY OF THE INVENTION

It is therefore a primary objective of the present disclosure to providea radio-frequency module and a wireless device capable of maintainingdata rate and/or performance and lowering power consumption.

An embodiment of the present disclosure provides a wireless device. Thewireless device includes a radio-frequency (RF) module and a modemmodule and a control unit. The RF module and the modem module operateeither in a first operation mode or in a second operation mode. Thecontrol unit, coupled to the RF module and the modem module, generates acontrol signal to indicate the RF module and the modem module to operatein the first operation mode or in the second operation mode. A first setof signal formats corresponding to the first operation mode is asuperset of a second set of signal formats corresponding to the secondoperation mode, and a first power consumption corresponding to the firstoperation mode is higher than a second power consumption correspondingto the second operation mode.

An embodiment of the present disclosure provides an RF module. The RFmodule includes a low noise amplifier (LNA), a first mixer, asynthesizer and a power amplifier (PA). The first fixer is coupled tothe LNA, in which the LNA and the first mixer process a first receivedRF signal in a first set of signal formats. The PA is coupled to thesynthesizer. The synthesizer and the PA generate a first transmitted RFsignal in a second set of signal formats, and the first set of signalformats is a superset of the second set of signal formats.

An embodiment of the present disclosure provides an RF module. The RFmodule includes a front-end circuit, a synthesizer, and a first PA. Thefront-end circuit generates a first transmitted RF signal in a first setsignal formats and process a first received RF signal in the first setof signal formats. The first PA is coupled to the synthesizer. Thesynthesizer and the first PA are configured to generate a secondtransmitted RF signal in a second set of signal formats. The front-endcircuit is disabled if the synthesizer is activated, and the first setof signal formats is a superset of the second set of signal formats.

These and other objectives of the present disclosure will no doubtbecome obvious to those of ordinary skill in the art after reading thefollowing detailed description of the preferred embodiments that areillustrated in the various figures and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a wireless device according to anembodiment of the present disclosure.

FIG. 2 is a schematic diagram of a wireless device according to anembodiment of the present disclosure.

FIG. 3 is a schematic diagram of a wireless device according to anembodiment of the present disclosure.

DETAILED DESCRIPTION

Reference is made to FIG. 1. FIG. 1 is a schematic diagram of a wirelessdevice 10 according to an embodiment of the present disclosure. Thewireless device 10 may be a Bluetooth device, operating within awireless personal area network (WPAN) system, which may comply withBluetooth standards/specifications. For devices within a WPAN system,power consumption is an issue for the wireless device, given the factthat the wireless device 10 may utilize a battery for supplying itselectricity power. To spare electricity power, the wireless device 10 isable to alternatively operate in a first operation mode, e.g., dual mode(legacy mode and low energy mode), or in a second operation mode, e.g.,a low energy (LE) mode. That is, the wireless device 10 transmits orreceives RF signals in a first set of signal formats if the wirelessdevice 10 operates in the first operation mode, and the wireless device10 transmits or receives RF signals in a second set of signal formats ifthe wireless device 10 operates in the second operation mode, in whichthe first set of signal formats is a superset of the second set ofsignal formats. Baseband signals corresponding to the RF signals in thefirst set of signal formats may include Gaussian frequency shift keying(GFSK) modulated signals and differential phase shift keying (DPSK)modulated signals, e.g., differential quadrature phase-shift keying (π/4DQPSK) modulated signals or differential 8-phase shift keying (D8PSK)modulated signals. Baseband signals corresponding to the RF signals inthe second set of signal formats may be Gaussian frequency shift keying(GFSK) modulated signals. To lower the consumed power, the wirelessdevice 10 is capable of dynamically switching between the firstoperation mode and the second operation mode, depending on the protocolrequirement, how much data needed to be transmitted/received (i.e., thedata rate) and/or the performance, e.g. signal quality, circuitlinearity, noise, interference tolerance, required by applications.

In detail, as shown in FIG. 1, the wireless device 10 comprises acontrol unit 12, a radio-frequency (RF) module 14, a modem module 16 andan antenna module 18. The control unit 12, coupled to the RF module 14and the modem module 16, is configured to determine which operation modethe wireless device 10 should operate in and to generate a controlsignal CTRL, to indicate the RF module 14 and the modem module 16 eitherto operate in the first operation mode or in the second operation mode.The RF module 14 and the modem module 16 are configured to generate orprocess the RF signals in the first set of signal formats, e.g., RFsignals corresponding to the π/4 DQPSK, D8PSK or GFSK modulated basebandsignals, while operating in the first operation mode, and to generate orprocess the RF signals in the second set of signal formats, e.g., RFsignals corresponding to the GFSK modulated signals, in the secondoperation mode. The modem module 16, comprising modem units 160 and 162,is configured to generate/process digital data corresponding to the RFsignals generated/processed by the RF module 14. The antenna module 18is configured to transmit the RF signals toward the air or to receivethe RF signals from the air.

In some embodiments, the control signal CTRL may be at least one controlcommand.

Specifically, in the current embodiment, the RF module 14 comprises afirst front-end circuit 14 a and a second front-end circuit 14 b, wherethe first front-end circuit 14 a is configured to generate or processthe RF signals in the first set of signal formats, and the secondfront-end circuit 14 b is configured to generate or process the RFsignals in the second set of signal formats. Notably, in order to savepower, if the control unit 12 indicates the RF module 14 and the modemmodule 16 to operate in the second operation mode, the first front-endcircuit 14 a is disabled or turned off.

In some embodiments, the control unit 12 determines which mode tooperate in according to at least one of a power factor and a performancefactor. The power factor maybe the power consumed by the wireless device10 or by the front-end circuits 14 a/14 b, and the performance factormay be the received signal quality (e.g., SNR), circuit linearity,noise, interference tolerance or the combination thereof.

Furthermore, as shown in FIG. 1, the first front-end circuit 14 acomprises a power amplifier (PA) 140 a, a low noise amplifier (LNA) 142a, a mixer 144 a, a mixer 146, filers 141 and 143 a, a digital-to-analogconverter (DAC) 145 and an analog-to-digital converter (ADC) 147 a. TheDAC 145, the filter 141, the mixer 146 and the PA 140 a, receivingdigital data, e.g., the π/4 DQPSK or D8PSK or GFSK modulated basebandsignals, from the modem unit 160, may generate a first transmitted RFsignal in the first set of signal formats, such that the antenna module18 may transmit the first transmitted RF signal in the first set ofsignal formats toward the air. On the other hand, the antenna module 18may receive a first received RF signal in the first set of signalformats from the air. The LNA 142 a, the mixer 144 a, the filter 143 a,and the ADC 147 a may process the first received RF signal in the firstset of signal formats, so as to generate received digital data to themodem unit 160 according to the first received RF signal in the firstset of signal formats.

In addition, the second front-end circuit 14 b comprises a PA 140 b, anLNA 142 b, a mixer 144 b, a synthesizer 148, a filter 143 b and an ADC147 b. Similarly, the synthesizer 148 and the PA 140 b, receivingdigital data (e.g., the GFSK modulated signals) from the modem unit 162,may generate a second transmitted RF signal in the second set of signalformats, such that the antenna module 18 may transmit the secondtransmitted RF signal in the second set of signal formats toward theair. The antenna module 18 may receive a second received RF signal inthe second set of signal formats from the air. The LNA 142 b, the mixer144 b, the filter 143 b and the ADC 147 b process the second received RFsignal in the second set of signal formats, so as to generate receiveddigital data to the modem unit 162 according to the second received RFsignal in the second set of signal formats.

Regarding the modem module, in one embodiment, the modem unit 160 isconfigured to generate/process signals based on DPSK and GFSKmodulation, and the modem unit 162 is configured to generate/processdigital data based on GFSK modulation.

In another embodiment, the modem unit 160 is configured togenerate/process digital data based on DPSK and GFSK modulation, and themodem unit 162 is configured to generate digital data based on GFSKmodulation and to process digital data based on DPSK and GFSKmodulation.

In some embodiments, the modem units 160 and 162 may be a single modemunit configured to generate/process digital data based on DPSK and GFSKmodulation.

Notably, the first front-end circuit 14 a, utilized to generate orprocess the RF signal in the first set of signal formats may achievebetter performance in terms of signal quality, circuit linearity, noisesensitivity, interference tolerance, etc., and/or may require moretransmission power. In this case, the RF module 14 would consume morepower while operating in the first operation mode. To bypass the powerconsumption disadvantage, if the RF module 14 and the modem module 16are switched to the second operation mode, the first front-end circuit14 a is disabled or turned off, and the RF module 14 only uses thesecond front-end circuit 14 b to transmit/receive the RF signals in thesecond set of signal formats, so as to reduce power consumed by the RFmodule 14.

In addition, the control unit 12 may determine whether to switch to thefirst operation mode from the second operation mode, or whether toswitch to the second operation mode from the first operation mode. In anembodiment, the wireless device 10 may operate in the second operationmode while the wireless device 10 is waiting to be connected. Once thewireless device 10 is connected to another device and there are enhanceddata rate (EDR) packets needed to be transmitted, e.g., an upgradeservice, a file with large size or voice/audio service that requires tobe transmitted in EDR packets, the control unit 12 may indicate the RFmodule 14 and the modem module 16 to operate in the first operation mode(through the control signal CTRL). After the transmission of EDR packetsis completed, the control unit 12 may indicate the RF module 14 and themodem module to switch back to the second operation mode. At this time,the second front-end circuit 14 b is activated, and the first front-endcircuit 14 a may be disabled or turned off, so as to reduce powerconsumption.

In some embodiments, the wireless device 10 may normally operate in thesecond operation mode. Once the control unit 12 detects that a data rateof the wireless device is insufficient to maintain the current wirelessconnection/link, the control unit 12 may indicate the RF module 14 andthe modem module 16 to operate in the first operation mode (through thecontrol signal CTRL). After the demand of the data rate is lowered suchthat the data rate in the second operation mode is sufficient, thecontrol unit 12 may indicate to the RF module 14 and the modem module 16to switch back to the second operation mode. Again, at this time, thesecond front-end circuit 14 b and modem unit 162 are activated, and thefirst front-end circuit 14 a and the modem unit 160 may be disabled orturned off, so as to reduce power consumption.

In some embodiments, the receiver 14 b and modem units 162 may be ableto receive a superset of the second set of signal formats, e.g., thefirst set of signal formats. Therefore, if the control unit 12 detectsthat it is required to receive signals in the first set of signalformats, e.g., EDR and non-EDR packets, and to transmit signals only inthe second set of signal formats, the control unit 12 activates thesecond operation mode.

In some embodiments, the first operation mode can be used only fortransmitting packets, e.g., EDR packets, including signals in the firstset of signal formats but not in the second set of signal formats, e.g.,DPSK modulated signals, and packets in the second set of signal formatse.g., non-EDR packets, are transmitted in the second operation mode. Bythis way of per-packet mode switch, the power consumption could befurther reduced.

In some embodiments, the mixers 146, 144 a and 144 b may be coupled toone or more synthesizers (not shown in FIG. 1) for receiving oscillatorsignals to up-convert baseband signals to radio frequency, or todown-convert RF signals to the baseband. In some embodiments, the mixers146, 144 a and 144 b may be coupled to the synthesizer 148 to receivethe oscillator signal(s) to up-convert the baseband signals or todown-convert the RF signals.

FIG. 2 is a schematic diagram of a wireless device 20 according to anembodiment of the present disclosure. The wireless device 20 is similarto the wireless device 10, and thus, the same components are denoted bythe same notations. Compared to the wireless device 10, the wirelessdevice 20 comprises an RF module 24, and the RF module 24 comprises thefirst front-end circuit 24 a and the synthesizer 148. Within the RFmodule 24, the synthesizer 148 is coupled to the PA 140 a within thefirst front-end circuit 24 a. If the RF module 24 operates in the secondoperation mode, the synthesizer 148 and the PA 140 a generate atransmitted RF signal in the second set of signal formats (e.g., RFsignals corresponding to the GFSK signals), according to the digitaldata from the modem module 16, such that the antenna module 18 transmitsthe transmitted RF signal in the second set of signal formats toward theair. On the other hand, the LNA 142 a, the mixer 144 a, the filter 143 aand the ADC 147 a may process RF signals in the second set of signalformats, and generate the received data in the baseband accordingly.Notably, in the second operation mode, there is no need for the DAC 145,the filter 141 and the mixer 146 to perform operations, and thus, theDAC 145, the filter 141 and the mixer 146 may be disabled or turned offif the RF module 24 operates in the second operation mode or if thesynthesizer 148 is activated, so as to reduce power consumption of thewireless device 20.

On the other hand, if the RF module 24 operates in the first operationmode, the first front-end circuit 24 a is activated, and the RF module24 is able to transmit and/or receive the RF signals in the first set ofsignal formats. Operations of the wireless device 20 operating in thefirst operation mode is the same as the wireless device 10, which is notnarrated herein for brevity.

In some embodiments, the mixers 144 a and 146 may be coupled to one ormore synthesizers (not shown in FIG. 2) for receiving oscillator signalsto down-convert RF signals to baseband signals or to up-convert basebandsignals to RF signals. In some embodiments, the mixers 144 a and 146 maybe coupled to the synthesizer 148 to receive the oscillator signal(s) todown-convert the RF signals or to up-convert the baseband signals.

In some embodiments, the first operation mode can be used only fortransmitting packets, e.g., EDR packets, including signals in the firstset of signal formats but not in the second set of signal formats, e.g.,DPSK modulated signals, and packets in the second set of signal formats,e.g., non-EDR packets, are transmitted in the second operation mode. Bythis way of per-packet mode switch, the power consumption could befurther reduced.

FIG. 3 is a schematic diagram of a wireless device 30 according to anembodiment of the present disclosure. The wireless device 30 isconfigured to receive the low-rate and high-rate data signals and totransmit only the low-rate control signals. For example, the wirelessdevice 30 may be a Bluetooth headset. The wireless device 30 is similarto the wireless device 20, and thus, the same components are denoted bythe same notations. Compared to the wireless device 20, the wirelessdevice 30 comprises an RF module 34, and the RF module 34 only comprisesthe synthesizer 148, the PA 140 a, the LNA 142 a, the mixer 144 a, thefilter 143 a and the ADC 147 a. Within the RF module 34, the synthesizer148 is coupled to the PA 140 a as well. To transmit the low-rate controlsignals (e.g., GFSK modulated signals), the synthesizer 148 and the PA140 a generate a transmitted RF signal in the second set of signalformats. To receive the low-rate and high-rate data signals, the LNA 142a, the mixer 144 a, the filter 143 a and the ADC 147 a are activated toprocess the received RF signals in the first set of signal formats(e.g., the π/4 DQPSK, D8PSK modulated signals and GFSK signals), andgenerate the received digital data accordingly. In addition, the LNA 142a, the mixer 144 a, the filter 143 a and the ADC 147 a may also beutilized to process the RF signals in the second set of signal formats,and generate the received digital data accordingly.

In some embodiments, the mixer 144 a may be coupled to one or moresynthesizers (not shown in FIG. 3) for receiving oscillator signals todown-convert RF signals to baseband signals. In some embodiments, themixer 144 a may be coupled to the synthesizer 148 to receive theoscillator signal(s) to down-convert the RF signals.

In some embodiments, the first set of signal formats and the secondsignal formats may be the same, in which the first set of signal formatsis also the superset of the second set of signal formats. In oneembodiment, the wireless device is similar to the wireless device 10shown in FIG. 1, in which the difference is that the frond-end circuits14 a and 14 b are both configured to transmit signals only in the secondset of signal formats, and transmit power/performance of the frond-endcircuit 14 a is larger/better than the one of the frond-end circuit 14b. In another embodiment, the structure of the RF module in the wirelessdevice comprises a first front-end circuit and a second front-endcircuit both similar to the frond-end circuit 14 a or 14 b in FIG. 1. Inone embodiment, the LNA in the first frond-end circuit has betterlinearity and noise figure compared to the LNA in the second front-endcircuit. In one embodiment, the mixer in the first frond-end circuit hasbetter linearity and noise figure compared to the mixer in the secondfrontend circuit. In one embodiment, the synthesizer coupled to themixer in the first frond-end circuit has less phase noise compared tothe synthesizer in the second front-end circuit. In one embodiment, thefilter of the receiver in the first front-end circuit has lessdistortion and better interference rejection compared to the filter ofthe receiver in the second frond-end circuit. In the embodiments above,the control unit 12 determines which mode to operate in according to atleast one of a power factor and a performance factor, in which the powerfactor maybe the power consumed by the wireless device or the powerconsumed by the frond-end circuit, and the performance factor may be thereceived signal quality (e.g., SNR), circuit linearity, noise orinterference tolerance.

In summary, the RF module and the wireless device of the presentdisclosure may operate in the first operation mode (in which thewireless device achieves higher data rate and/or better performance,e.g., signal quality, circuit linearity, noise sensitivity, interferencetolerance, but consumes more power) or operate in a second operationmode (in which the wireless device keeps power consumption low but thedata rate and/or performance thereof is sufficient), so as to maintainthe required performance and to keep the power consumption as low aspossible.

Those skilled in the art will readily observe that numerousmodifications and alterations of the device and method may be made whileretaining the teachings of the invention. Accordingly, the abovedisclosure should be construed as limited only by the metes and boundsof the appended claims.

What is claimed is:
 1. A wireless device, operating within a wirelesssystem, the wireless device comprising: a radio-frequency (RF) moduleand a modem module, configured to operate in a first operation mode orin a second operation mode; and a control unit, coupled to the RF moduleand the modem module, configured to generate a control signal toindicate the RF module and the modem module to operate in the firstoperation mode or to operate in the second operation mode; wherein afirst set of signal formats corresponding to the first operation mode isa superset of a second set of signal formats corresponding to the secondoperation mode, and a first power consumption corresponding to the firstoperation mode is higher than a second power consumption correspondingto the second operation mode; wherein the RF signals in the first set ofsignal formats correspond to frequency shift keying (FSK) modulatedbaseband signals and phase shift keying (PSK) modulated basebandsignals; wherein the RF signals in the second set of signal formatscorrespond to FSK modulated baseband signals, or the RF signals in thesecond set of signal formats correspond to FSK modulated basebandsignals and PSK modulated baseband signals.
 2. The wireless device ofclaim 1, wherein the RF module generates or processes RF signals in thefirst set of signal formats if the RF module operates in the firstoperation mode, and the RF module generates or processes RF signals inthe second set of signal formats if the RF module operates in the secondoperation mode.
 3. The wireless device of claim 2, wherein the RFsignals in the first set of signal formats correspond to GaussianFrequency shift keying (GFSK) modulated baseband signals anddifferential phase shift keying (DPSK) modulated baseband signals, andthe RF signals in the second set of signal formats correspond toGaussian frequency shift keying (GFSK) modulated baseband signals. 4.The wireless device of claim 2, wherein the RF module comprises: a firstfront-end circuit, configured to generate and process the RF signals inthe first set of signal formats; and a second front-end circuit,configured to generate and process the RF signals in the second set ofsignal formats; wherein the first front-end circuit is disabled if theRF module operates in the second operation mode.
 5. The wireless deviceof claim 4, wherein the first front-end circuit comprises: a firstmixer; a first power amplifier (PA), coupled to the first mixer; a firstlow noise amplifier (LNA); and a second mixer, coupled to the first LNA;wherein the first mixer and the first PA are configured to generate theRF signals in the first set of signal formats, and the first LNA and thesecond mixer are configured to receive and process the RF signals in thefirst set of signal formats.
 6. The wireless device of claim 4, whereinthe second front-end circuit comprises: a synthesizer; a second PA,coupled to the synthesizer; a second LNA; and a third mixer, coupled tothe second LNA; wherein the synthesizer and the second PA are configuredto generate the RF signals in the second set of signal formats, and thesecond LNA and the third mixer are configured to receive and process theRF signals in the second set of signal formats.
 7. The wireless deviceof claim 2, wherein the RF module comprises: a first mixer; a poweramplifier, coupled to the first mixer; a second mixer; a low noiseamplifier, coupled to the second mixer; and a synthesizer, coupled tothe power amplifier, the first mixer, and the second mixer; wherein thefirst mixer and the power amplifier generate the RF signals in the firstset of signal formats when the RF module operates in the first operationmode, and the synthesizer and the power amplifier generate the RFsignals in the second set of signal formats when the RF module operatesin the second operation mode; wherein the first mixer is disabled whenthe RF module operates in the second operation mode.
 8. The wirelessdevice of claim 7, the RF module further comprises: a digital-to-analogconvertor (DAC); and a filter, coupled between the DAC and the firstmixer; wherein the DAC and the filter are is disabled if the RF moduleoperates in the second operation mode.
 9. The wireless device of claim2, wherein the RF module comprises: a power amplifier (PA); a mixer; alow noise amplifier (LNA), coupled to the mixer; and a synthesizer,coupled to the power amplifier; wherein the synthesizer and the PAgenerate the RF signals in the second set of signal formats, and the LNAand the mixer process the RF signals in the first set of signal formatsand the second set of signal formats.
 10. The wireless device of claim1, wherein the RF module generates RF signals in the second set ofsignal formats and processes RF signals in the first set of signalformats if the RF module operates in the second operation mode.
 11. Thewireless device of claim 10, wherein the RF signals in the first set ofsignal formats correspond to Gaussian Frequency shift keying (GFSK)modulated baseband signals and differential phase shift keying (DPSK)modulated baseband signals, and the RF signals in the second set ofsignal formats correspond to Gaussian frequency shift keying (GFSK)modulated baseband signals.
 12. The wireless device of claim 1, whereinthe RF module generates RF signals in the first set of signal formats ifthe RF module operates in the first operation mode, and the RF signalsin the first set of signal formats correspond to Gaussian Frequencyshift keying (GFSK) modulated baseband signals and differential phaseshift keying (DPSK) modulated baseband signals.
 13. The wireless deviceof claim 1, wherein the wireless system is a wireless personal areanetwork (WPAN) system.
 14. The wireless device of claim 1, wherein thewireless system complies with a Bluetooth standard, the first operationmode is an enhance data rate (EDR) operation mode under the Bluetoothstandard, and the second operation mode is a low energy (LE) mode underthe Bluetooth standard.
 15. A radio-frequency (RF) module, comprising: alow noise amplifier (LNA); a first mixer, coupled to the LNA, whereinthe LNA and the first mixer are configured to process a first receivedRF signal in a first set of signal formats; a synthesizer; and a poweramplifier (PA), coupled to the synthesizer, wherein the synthesizer andthe PA are configured to generate a first transmitted RF signal in asecond set of signal formats; wherein the first set of signal formats isa superset of the second set of signal formats.
 16. The RF module ofclaim 15, further comprising: a second mixer, coupled to the PA; whereinthe second mixer and the PA are configured to generate a secondtransmitted RF signal in the first set of signal formats; wherein thesecond mixer is disabled when the synthesizer is activated.
 17. The RFmodule of claim 15, wherein the RF signals under the first set of signalformats correspond to Gaussian Frequency shift keying (GFSK) modulatedbaseband signals and differential phase shift keying (DPSK) modulatedbaseband signals, and the RF signals under the second set of signalformats correspond to Gaussian frequency shift keying (GFSK) modulatedbaseband signals.
 18. A radio-frequency (RF) module, comprising: afront-end circuit, configured to generate a first transmitted RF signalin a first set of signal formats and process a first received RF signalin the first set of signal formats; a synthesizer; and a first PA,coupled to the synthesizer, wherein the synthesizer and the first PA areconfigured to generate a second transmitted RF signal in a second set ofsignal formats; wherein the front-end circuit is disabled if thesynthesizer is activated.
 19. The RF module of claim 18, wherein thefront-end circuit comprises: a first mixer; a second power amplifier(PA), couple to the first mixer, wherein the first mixer and the secondPA are configured to generate the first transmitted RF signal in thefirst set of signal formats; a low noise amplifier (LNA); a secondmixer, coupled to the LNA, wherein the LNA and the second mixer areconfigured to process the first received RF signal in the first set ofsignal formats.
 20. The RF module of claim 18, wherein the RF signalsunder the first set of signal formats correspond to Gaussian Frequencyshift keying (GFSK) modulated baseband signals and differential phaseshift keying (DPSK) modulated baseband signals, and the RF signals underthe second set of signal formats correspond to Gaussian frequency shiftkeying (GFSK) modulated baseband signals.